MyomiRNAs and myostatin as physical rehabilitation biomarkers for myotonic dystrophy

MiR-1 and myostatin are markers for muscle growth and regeneration. Myostatin has a key role in the regulation of muscle mass. Myotonic dystrophy type 1(DM1) patients have a disease-specific serum miRNA profile characterized by upregulation of miR-1, miR-206, miR-133a, and miR-133b (myomiRNAs). This study aims to evaluate the possible utility of myomiRs and myostatin as biomarkers of rehabilitation efficacy in DM1, supporting clinical outcomes that are often variable and related to the patient’s clinical condition. In 9 genetically proven DM1 patients, we collected biological samples before (T0) and after (T1) exercise rehabilitation training as biological measurement. We measured serum myomiRNAs by qRT-PCR and myostatin by ELISA test. The clinical outcomes measures that we utilized during a 3–6 week rehabilitation controlled aerobic exercise period were the 6-min walking test (6MWT) that increased significantly of 53.5 m (p < 0.0004) and the 10-m walk test (10MWT) that decreased of 1.38 s. We observed, after physical rehabilitation, a significant downregulation of myomiRNAs and myostatin that occurred in parallel with the improvement of clinical functional outcome measures assessed as endurance and gait speed, respectively. The modulation of biomarkers may reflect muscle regeneration and increase muscle mass after aerobic exercise. miRNAs and myostatin might be considered as circulating biomarkers of DM1 rehabilitation. The efficacy of physical rehabilitation in counteracting molecular pathways responsible for muscle atrophy and disease progression and the role of these biomarkers in DM1 and other neuromuscular diseases warrant further investigation.